Microbiology & Immunology, The University of Western Australia, Nedlands 6009, Western Australia, Australia.
Division of Microbiology & Infectious Diseases, PathWest Laboratory Medicine, Nedlands 6009, Western Australia, Australia.
J Med Microbiol. 2011 Aug;60(Pt 8):1108-1111. doi: 10.1099/jmm.0.031062-0. Epub 2011 Mar 10.
A total of 817 human clinical isolates of Clostridium difficile from all Australian states were screened for A(-)B(+) strains by toxin gene PCR assays. Nine (1.1 %) strains were confirmed to be A(-)B(+) by enzyme immunoassay for toxin production. Of these, six (66.7 %) were binary toxin-positive by PCR. Using PCR ribotyping and toxinotyping, the A(-)B(+) strains could be grouped into seven ribotypes and three toxinotypes. Only one of the ribotypes had been reported previously (017). The prevalence of ribotype 017 was low in this study with only two strains detected. Two new A(-)B(+) toxinotypes were also defined (XXX, XXXI). Toxinotype XXX had a toxin B gene similar to that of toxinotype IV (A(+)B(+)) but with a novel cytopathic region. Toxinotype XXXI was similar to other A(-)B(+) types (X, XVII), but had a larger deletion to the toxin A gene than in either of those types. The types of A(-)B(+) strains identified in this study differed markedly from those described in other regions.
从澳大利亚所有州的 817 株艰难梭菌临床分离株中，通过毒素基因 PCR 检测法筛选 A(-)B(+) 株。酶免疫分析法检测到 9 株（1.1%）菌株产毒素呈 A(-)B(+)。其中 6 株（66.7%）经 PCR 检测为二元毒素阳性。通过 PCR 核糖体分型和毒素分型，A(-)B(+) 株可分为 7 种核糖体型和 3 种毒素型。只有一种核糖体型之前有报道（017）。在本研究中，017 核糖体型的流行率较低，仅检测到两株。还定义了两种新的 A(-)B(+)毒素型（XXX、XXXI）。毒素型 XXX 的毒素 B 基因与毒素型 IV（A(+)B(+)）相似，但具有一个新的细胞病变区。毒素型 XXXI 与其他 A(-)B(+)型相似（X、XVII），但与这两种类型相比，毒素 A 基因缺失更大。本研究中鉴定的 A(-)B(+) 菌株类型与其他地区描述的类型明显不同。
